I'd get an F too. I also only use rear wheel lock. Although I think I have that teddy bear luck going on. I usually have two kid helmts hanging off the handle bars ( yeah I leave those too!) and I think the person would go to hell for taking my stuff... and I have weight going on. ( I know someone whose dutch bike was stolen sort of with rear wheel lock. It was so heavy that the guy ended up throwing bike in the bushes two doors down. and that was in a more bike theft savy area too...